Typewriting machine



Sept. 27, 1938.

' w. A. DOBSQN TYPEWRITING MACHINE p 1938- V w. A. DOBSON V 2,131,135

' TYPEWRITING MACHINE Filed Dec. 14, 1934 I 3 Sheets-Sheet 2 V In um for:

W UAW/W I Affqrn Sept. 27, 1938. w. A. DOBSON TYPEWRITING MACHINE Filed Dec, 14, 1954 3 Sheets-Sheet 3 head.

Patented Sept. 27, 1938 UNITED STATES 2,131,135 TYPEWRITING MACHINE William A. Dobson,

Wethersfield, Conn., assignor to Underwood Elliott Fisher Company, New York, N. Y., a corporation of Delaware Application December 14, 1934, Serial No. 757,515

Claims. (on. 19-1-25) This invention relates to type-actions, and deals with the class of front-strike noiseless type-actions in which a type-key, a pressure-printing toggle, and a momentum-accumulating flyweight co-operate to control the type-carrier.

An object of the invention is to produce such a type-action by a combination of a minimum number of parts, in order to simplify the typeaction and its operation and to reduce the cost of manufacturing and servicing the typewriter.

Another object of the invention is to have such simplification of the type-action also conduce to greater ease of key-touch and to clear and quietly-efiecte'd printing and manifolding.

A further advantage of the contemplated novel type-action is that it may be compacted, and it is therefore particularly useful for typewriters of the portable class.

To these and other ends, there is employed, in the improved type-action, a type-carrier that is preferably a bar which carries the type at one end, and is fulcrumed at its other end for swinging movements.

Excepting the type-key-levers, which may'extend parallelly fore and aft the machine, the several typeactions of the printing system radiate forwardly and laterally from the printing point; the type-bars being normally partly erect in an arcuate array confronting the platen, since in said array they are inclined, about the fulcrum-axis, upwardly and away from the printing point.

Each type-bar has connected thereto at a point near the type-head one of a pair of toggle-links, the other toggle-link reacting against a fixed fulcrum that is ubstantially in front of the typethe type-head against the platen; and in the normal, that is, idle, forwardly tilted position of the type-bar, said toggle-links are in suppressed folded position betweenthe type-bar and said fixed toggle-fulcrum.

A secondary toggle, which includes a fly weight, has one of its links pivotally connected to a point between the ends of the forward link of the primary or pressure-printing toggle, and has its other link upstanding from a fixed fulcrum below the fixed fulcrum of the primary toggle. One of the secondary toggle-links may have an enlargement that serves as the momentum-accumulating fiy-weight.

The forward link of the primary toggle is thus a lever upon which the secondary toggle acts, under the impulse of the fly-weight momentum, to straighten the primary toggle for pressing the type against the platen.

According to the invention, said forward link the printing point to press of the primary toggle is also utilized as a lever primarily acted upon by the type-key-lever through a simple link. For this purpose, said forward link of the primary toggle has, extending forwardly from the fixed fulcrum, an operating arm to which the upper end of said simple link is connected; the lower end of the link being connected to the key-lever which extends fore and aft of the machine, and is below the assem- "blage that is in radial relation to the printing point and comprises the type-bar and the primary and secondary toggles. I

Since the primary toggle is provided with the aforesaid operating arm that is directly linked to the type-key-lever, the secondary'toggle has nothing to do with starting the unfolding of the type-bar and primary toggle-links. Said secondary toggle therefore may be, in its normal position, in the most compactly folded relation I to the primary toggle and its fixed fulcrum.

Moreover, the operating arm of theprimary toggle, directly connected to the type-key-lever,

is arranged so that it has a maximum leverage moment at the beginning of the printing stroke, because the leverage moment may decrease throughout the printing stroke, as the type-action, mainly under the impulse of the fly-weight device, gains in momentum during said stroke. The maximum and decreasing leverage moment gained bysuch arrangement of the primary toggle-operating arm conduces greatly to ease of key-touch; while the provision of said primary toggle-operating arm and itssimple link-connection to they key-lever also results in minimizing the number of parts in the type-action, and makes the compacting of the type-action feasible. It further results from the provision of the primary toggle-operating arm and its simple link-connection to the key-lever that the only portion of the type-action that is below the lower or fulcrum ends of the type-bar and of the aforesaid upstanding link of the fly-weight toggle, is the key-lever/ It is feasible, therefore, to dispose said fulcrum ends low enough so that,

correspondingly, the array of type-heads, and certain contiguous parts of the framework are disposed at a minimized elevation. This feature is an important desideratum in portable typewriters, and it also conduces to visibility of the printing line.

Since the type-bars and toggles radiate from the printing point,'the forwardly-extending primary toggle-operating arms will diverge to points that are sufficiently close to the planes of their respective key-levers to make connection of the latter to said operating arms aforesaid simple links feasible. For this purpose, the key-levers themselves may be provided 'with portions or'branches to .which the links are connected and which are bent inwardly, from the by means of the main fore-and-aft-extending portions, to effect alignments of the links substantially within the. planes of the primary toggle-operating arms.

The main fore-and-aft-extending portion of a key-lever may pass below the inwardly-bent portion of an adjacent key-lever so as to avoid interference.

The key-levers may have their printing-strokes arrested, just before the instant of printing, by a noiseless stop; the action of the secondary toggle and fly-weight being permitted to continue by momentum to complete the straightening ac tion uponthe primary toggle to press the type forcibly,but quietly, against the work upon the platen. Simple provision may be made for idle play in the link-connection between the aforesaid primary toggle-operating arm and the typekey-lever to permit the continuing action of the type-bar and toggles after the printing-stroke of the key-lever has been thus arrested. Other sound-deadeningstops may be provided for limiting the action of the toggles in the printing and return strokes.

Other features and advantages will hereinafter appear.

In the accompanying drawings,

Figure 1 is a side view showing mainly the middle one of the novel type-actions in normal, idle position, some of the related parts being shown in section.

Figure 2 is a side-view diagram illustrating the,

positions of the parts of the novel type-action at the initial portion of the return stroke which follows the printing.

Figure 3 is a diagram illustratingin full lines the positions of the parts of the type-action at the instant when the printing-stroke of the key-lever has been arrested, whereupon, as indicated by the dotted lines, a fiy-weight becomes eifective to straighten the primary toggle to press the type against the platen.

Figure 4 is a side view showing mainly one of the novel type-actions that is at the side of the printing-system, the middle type-action being fragmentarily shown.

Figure 5 is a side-view diagram illustrating a key-lever detail which provides for detachable connection to the key-lever of the link extending from the primary toggle-operating arm.

Figure 6 is a side-view diagram illustrating the manner of manipulating the parts to effect connection or disconnection of the link and keylever of Figure 5. v

Figure 7 is a top-plan view showing only the left half of the type-action system, the right half being substantially the same, Parts are omitted or are shown broken away for clearness.

Type-keys ID are mounted upon key-levers which extend rearwardly to a fulcrum l2, and

are transversely spaced by rear and front guidecombs l3 and I4. The normal positions of the key-levers are determined by a transverse sounddeadening stop l6 upon the front comb-plate |4'. Each key-lever has a spring I! for yieldably upholding it against said stop l6.

The key-levers II are operatively related to type-carriers |8 by means of an organization which is simple and compact, and which, nevertheless, comprises fully suificient means for clearly and quietly printing and manifolding by momentum-controlled pressure and an easy keytouch. To these and other ends, the novel typeaction organization is arranged'as follows:

The several type-carriers l8 are bars pivoted at one end upon a common fulcrum-wire20 of a segment 2| having type-bar-retain ing slots 22 that are in radial relation to printing-point 23 traversed by a platen 24 against which types 25 at the upper ends of said type-bars I print. The

type-bars i8thus work in planes radiating forwardly and laterally from the printing-point. In their normal, idle positions, as at. Figure 1, the type-bars are semi-erect in that they are inclined upwardly and away from the printing-point, and are disposed in an arcuate array confronting the platen and in which array the type-ends of the type-bars rest against an arcuate pad 26 mounted upon an upper segment 21. v

A primary pressure-printing toggle comprises a member or link 28 pivoted to the type-bar I! at a point 23 near the type-head. A second member or link 30 of the primary toggle works about a fixed fulcrum-wire 3| in the upper segment 21 which has radial slots 32 for retaining the forward links 30 of the primary toggle in radial disposition corresponding to the radial disposition of the type-bars I8. The primary toggle-links 28, 30 are pivotally joined at 33. In the idle, Figure 1 position of the type-bars l8, their toggles 28, 30 are in suppressed folded conditionbetween the type-bars I8 and the primary togglefulcrum 3|.

For unfolding and straightening the primary toggle 28, 30, to bring the type-bar l8 from its idle position to the platen, said toggle is primarily acted upon by the keylever H, and finally by a secondary toggle which will presently be described and which includes a fiy-weight device whose accumulated momentum acts to straighten said primary toggle to quietly press the type-bar and hence the type against the platen.

Simple and compact arrangement of the typeaction is effected by having the forward link 30 of the primary toggle first acted upon as a lever by the type-key-lever II, and then acted upon as the forward link 30 of 30 a lever by the secondary fly-weight toggle, said arrangement beingcarried out as follows:

An operating arm 35 is provided upon the forward link 30 of the primary toggle and extends, when the parts are in the idle, Figure 1 position, forwardly from the fixed primary toggle-fulcrum 3|. A pull-link 36 pivoted to said operating arm at 31 connects the latter to the key-lever II, the lower end of the link and the key-lever being articulated at 38.

The aforementioned secondary fly-weight toggle, included in each type-action, comprises a member or link 39 pivoted to the forward link 30 of the primary toggle at a point 40 between the ends of said link 30, as indicated in Figure 1. A second member or link 4| of the secondary flyweight toggle is upstanding from a fixed fulcrum-wire 42 presented by the segment 2| which has radial slots 43 in which the several upstanding links 4| are retained in radial disposition.

The secondary toggle-links 39, 4| are pivotally connected at 44, and the link 39 has an enlargement forming a fly-weight 45. Said fiy-weight is disposed so that in the unfolding of the secondmary toggle 28, 30 from the Figure 1 position,

ary toggle, started and maintained during the i but, at first, follows the unfolding of the primary toggle, the secondary toggle may be, when the parts are in idle position, completely folded and therefore compacted, inasmuch as the point 48 may be between and substantially in line with the points 42, 44, as shown in Figure 1. 8

Further advantage results from the provision of the operating arm 35 for the primary toggle, and its simple link-connection to the key-lever II, by pointingsaid arm 35, as indicated in Figures 1 and 4, so as to conduce to ease of keytouch. Comparing Figures 1 and 3, it will be seen that said operating arm 35 is pointed so 'that its leverage moment decreases from a maximum, when the parts are in the idle or Figure 1 position, to a least leverage moment, which obtains when the printing-stroke of the key-lever H has been arrested as in Figure 3, by a transverse sound-deadening stop 5| mounted on the combplate l4. Said maximum leverage moment of the operating arm '35 at the beginning of the keystroke conduces to the desired easy key-touch, it being understood that the decrease of leverage moment of the operating arm 35 during the printing-stroke is compensated for by the concurrent gain in momentum of the parts.

The direct connection of the key-lever to the primary toggle 28, 38, afforded by the operating arms 35 of the primary toggle and the link 36, not only makes the described compact folding of the secondary toggle feasible, but conduces otherwise to the compactness of the typeaction. Thus it will be noted that the key-levers H are the only type-action parts below the seg-' ment 2|, and that all the remainder of the typeaction system is compacted between said lower segment 2| and the upper segment 31. The space between said lower segment 2| and a line 48, representing the machine-base or a table, may, therefore, be freely utilized for disposing mechanism, such as ribbon-spool-driving mechanism,'

indicated at 41, Figure 1, in which 48 and 9 represent respectively a vertical ribbon-spool shaft and a ribbonspool. Furthermore, since there is nothing of the novel type-action system but the key-levers below the lower segment 2|, it

- becomes feasible to have the latter low with reference to the platen-axis and, correspondingly, to have the upper segment 21 and overlying array of type-heads 25 low enough to afford good visibility of the printing-line as indicated in Figure 1.

A spring 52 for each type-action may have other end connected to a loop 54 of the pull-link 36, said spring acting to aid in breaking the straightened primary and fly-weight toggles after the latter have acted to press the types against the platen. Said spring 52'a1so serves to prevent rattling of the link 36.

Since the operating arms 35 of the primary toggles radiate forwardlyand laterally from the printing-point, it will be seen that they diverge toward the planes of their associated key-levers H for connection of the latter by means of the links 36. To further the feasibility of such connection, the key-levers may have "branches 55 presenting the points, 38 to which said links 36 are articulated, said branches being bent, arranged and graded as best seen inFigure '7, to offset said points 38 inwardly from the bodies of the key-levers, and thereby bring said points. which are appropriately located fore and aft of type-action namely, the resultant dip of the point 38 the key-levers, toward the planes of the operating arms 35 to align the links 36 substantially within said planes. All except the few middle ones of the key-levers may have the described inward bending of the branches 55.

The depth of key-stroke at the several keybanks is made substantially uniform by grading the distances of stop-edges 58, Figure 1, of the key-leversfrom the key-lever-arrestlng stop 5|.- Thus, the key-levers of the foremost bank have their stop-edges 56 closer to the stop 5| than the next higher bank of keys, the stop-edges 58 for the key-levers of the rearmost bank being farthest from the stop 5|. It follows that the angular displacement of the key-levers will not be the same for the several key-banks, thekeylevers for the rearmost bank having the greatestangular displacement, and the foremost bank of key-levers having the least angular displacement.

Nevertheless, substantially uniform actuation of the type-bars and togglesthroughout the system is produced, by grading the locations of, the

points 38 at which the links 36 are connected tothe key-levers. It can be seen that the location of the point 38 along a branch 55-it being noted that the planes of branches 55 conform substantially to the planes of the operating arms 35- p determines the angular displacement of the operating arm 35 resulting from a given angular displacement of the key-lever II. The location of said point 38 determines not only its dip, but

also determines the angle at which the link 36 4 pulls with referenceto a line joining the points 3|, 31, of the operating arm 35; it being evident, for example, that the more forward of the point 31 the point 38 is along the branch 55, the closer will be the line of pull of the link 36 to said fulcrum 3| about which the toggle-member 30, which includes ithe operating arm 35, turns. Thus, the location of g the point 38 along the branch 55 involves two factors that are determinative of the throw of the toggle-member 30, and the resultant aforementioned link 36 pulls upon the operating arm 35.

The branch 55 of a key-lever may cross the plane of one or more adjoining key-levers as indicated in Figure 7, and, to make this feasible, each key-lever may extend to the key-leverfulcrum I2, by means of a reach 58 which is dropped angle at which the below the zone of the branches 55 by a pendent I portion 59 of the key-lever. As shown in Figure 7, the branches 55 may be bent from points 60 of the key-levers, so that the array of all the branches 5,5 approximates conformation to the arcuate and radial array in which the operating arms 35 are disposed by the upper segment 21. g

Figure 4 illustrates the extremesof location of the key-leverpendent portions 59 as between the key-lever for the type-action system and the key-lever for the middletype-action. To provide for vertical adjustment of the points 38, by bending the branches 55 up or down, said branches may be relieved from the bodies of the key-levers by undercuts 8| which are of maximum forward depth at the-middle of the system, and which may diminish in depth/toward the sides of the system, as indicated in Figures 1 and 4.

at the side of the The portion of the key-lever working in the ing in said comb-guide, sufflcient to counteract the eccentric reaction of the offset point 38.

The printing stroke of the key-lever is arrested by the stop I just before the type reaches the printing point, the parts of the type-action being then in the positions shown by the full lines in Figure 3. Thereupon the accumulated momentum of the fly-weight 45 acts through the secondary toggle 39, M, to complete the straightening of the primary toggle 28, 30, to press the type quietly against the platen, the position of the types, the primary toggle and the fly-weight at the instant of printing being indicated by the dotted outlines in Figure 3. In order that the type-bar I8 and toggles may thus complete their action independently of the key-lever II, the latter has a'loose connection, at the point 38, to the lower end of the link 36. The key-lever may accordingly be provided with an up-and down extending slot 62, whose upper end forms a shoulder around and under which the lower stirrup of said link 36 may be hooked, as indicated. Thus; after the key-lever has been arrested, as in Figure 3, the lower end of the link 36 may move down idly from the upper shoulder of the slot 62 as the type-bar and toggles continue their described, action under the impulse of the momentum of fly-weight 45.

To prevent overthrow of the toggles, the up'-- standing link 4| of each secondary toggle may have a shoulder 64 which, at the instant of printing, engages a stop-plate 65 to arrest the seconary toggle, and, through the latter, arrest the primary toggle 28, 30 in its straightened position indicated by the dotted outline, Figure 3. Said stop-plate 65 may rest upon a sound-deadening cushion 66, and may furthermore be of thin resilient material to conduce tothe sound-dead? ening.

The stop-plate 65 and underlying cushion 66 may be supported by the lower segment 2 I, and be secured to the latter by means of screws 61 and k a clamp-plate 68 arranged to leave the forward stopping rim of the stop-plate 65 exposed as indicated in Figures 1, 3 and '7.

The upstanding link 4! of the secondary toggle willtend to rebound after its-contact with the stop-plate 65, and will thus tend to break the secondary toggle, and through the latter break the primary toggle, immediately after the types have printed. The breaking of the toggles is aided by the above-described spring 52, and the effect of the latter may be reinforced by a spring 10, hooked into the loop 54 of the link 36, the other end being hooked into a skirt II of the upper segment 21. Use of the reinforcing springs may be limited to the type-actions associated with the rearmost bank of key-levers, since these typeactions have the shortest springs 52.

To facilitate connection and disconnection of the link 36and key-lever II, the latter may be arranged so that the link-articulating slot 62 is open at the bottom as at I2, Figures 5 and 6. The bottom stirrup of the link 36 may be entered into or withdrawn from the slot 62 by way of the opening at I2 when the key-lever II is in its normal position, while the vrest of the typeaction is manually held with the type at the platen as shown in Figure 6.

The upstanding link 4| of each secondary toggle may be doubled as shown at Figures 4 and 7, so that, for.pivotal connection to the fly-weight link 39, 45, it straddles the opposite sides of the latter. The fulcrum-end of each double link may straddle the opposite sides of a fin 14 formed by lever. -seen that the primary toggle 28, 30 will have the slots 43 of the segment 2|. A spacer at 53 where the spring 52 is connected is between the doubled parts of said link 4I.' The rear link 28 of the primary toggle may also be doubled, so that, for connection to the type-bar I8 and the forward toggle-link 30, it straddles opposite sides of these parts, as indicated in Figure 7.

To an under side 80 of the upper segment 21, there is attached a sound-deadening cushion 8| which serves to quietly arrest the return stroke,-

principally of the primary toggle 28, 30, by opposing the operating arm 35 of the latter, as shown toggles can operate at maximum efliciency for quiet and clear printing and manifolding. After the key-lever stroke has been easily started, by

reason of the provision of the operating arm 36 on the primary toggle and its link-connection to the key-lever, and, whenthe fly-weight mo-- mentum has taken over the bringing of the typebar I8 to the platen, there is nothing, because of said provision, to impede free action of the typebar and the toggles under the impulse of said momentum, since these are practically the only parts that work independently of the key-lever II, the simple link-connection 36 obviously causing no restraint upon said free action.

It will further be seen that the key-driven power-lever 30, co-operates with the togglelink 28 to smoothly accelerate and then decelerate the type-bar I8 relatively to said power-lever, and that while the type-bar is being decelerated during the printing stroke the fly-weight substantially continues to be speeded by said power-v Thus, referring to Figure 3, it will be served to gradually decelerate the type-bar so that the final movement of the latter from its indicated full-line position just before printing is non-percussive; and that during said final movement of the type-bar the fly-weight 45 is working at maximum efficiency, since during the deceleration of the type-bar relatively to said powerlever 30, 35, the latter substantially continues tospeed said fly-weight; and that these conditions conduce to easy key-touch and clear quiet printing and good manifolding'. I Variations may be resorted to within the scope of the invention, and portions of the improve--' ments may be used without others.

Having thus described my invention, I claim: 1. In a front-strike type-action system co-operative with a platen, a set of type-carriers working in planes radiating from the printing-point, a set of type-key-levers individually ranging substantially fore and aft of the machine and di posed below the typeecar'rlers', and a system of operating connections between saidv type-carriers and levers, said system ofconnections including operating levers disposed above the key-levers and working in planes' radiating forwardly and laterally from a given point, andlinks, one for each type-action, connecting said radial operat ing levers to corresponding type-key-levers, said radial operating levers presenting an arrayof operating arms diverging toward the planes of the corresponding type-key-levers, the latter having branches to which the links are connected, said branches being of different extents and being bent at different angles inwardly from the fore-and-aft-extending body-portions of said type-key-levers, to converge toward the planes of said operating arms, to provide for connecting said operating arms to said type-key-levers by said links. I

2. In a typewriting machine, a 'set of type-keylevers extending rearwardly from a banked keyboard to a common fulcrum-axis, stop-means to limit the key-lever movements to make the keystrokes of uniform depths throughout the several banks of the keyboard, a set of type-car riers, a toggle connected to each type-carrier and having an operating arm by means of which it is actuated to actuate the type-carrier, said type-carriers and toggles working in planes radiating forwardly and laterally from a common printing-point, and a system of links, one for each key-lever, connecting the latter to an operating arm provided on the toggle of the corresponding type-carrier, said key-levers having branches presenting points to which said links are connected, said branches ofisetting said points laterally from the body-portions of saidkey-levers to bring the links substantially within the planes of the radial toggle-operating arms, said type-carriers and toggles being substantially uniform throughout the system, while the keylevers of the several banks of the keyboard have different angular displacements by reason of their common fulcrum-axis, and uniform depths of key-strokes, the location of the points of connection of said links to the key-leversbeing further graded by means of said branches,. so that the different angular displacements of the key-levers produce uniform actuation of 'said toggles throughout the system.

3. In a typewriting machine having a platen, the combination with a system of type-carriers and members associated therewith, said members having operating arms by means of which they may be actuated to actuate the type-carriers, of a set of type-key-levers disposed below the system of type-carriers and associated mem-. bers, said key-levers extending substantially fore and aft of the machine, said type-carrier-actuatlng members being radially disposed with reference to the printing-point so that their oper-. ating arms diverge forwardly and laterally, to tend toward the planes of the corresponding keylevers, and links pendent from said operating arms and connecting the latter to appropriate points on the corresponding key-levers, the latter having branches of graded extents and laterally graded inclinations so as to present said points in graded, laterally ofiset relations to the fore-and-aft-extending body-portions of the keylevers and at different locations lengthwise of the latter, thereby to enable said links to work substantially within the planes of said operating 4. The invention as set forth in claim 3, said branches being differentially located along, and bent laterally from, the fore-and-aft-extendlng lgy-levers to form an array conforming substantially with the radial array of said type-carrier-actuating members, the fore-and-aft-extending body-portions of the key-levers being said branches crossing the body-portion of one or more adjacent, key-levers, but clearing the latter, at the key-strokes. by reason of said downwardly offset bodyportions.

5. In a typewriting machine, a type-action for printing quietly by means of pressure and a pressure controlling momentum accumulator, said type-action being constituted of a minimum number of parts by the combination 'of a typecarrier having type at one end and fulcrumed at the other end, a primary-toggle connected to the type-carrierand reacting against a fixed togglefulcrum, the toggle-member which engages said toggle-fulcrum having an operating arm by means of which 'said toggle may be actuated to actuate the type-carrier, and thereby cause the latterto print by the pressure exerted thereon by, actuation of said toggle, a typekey-lever, a link directly connecting said typekey-lever to said operating arm of said toggle, and a secondary toggle, including a momentumaccumulating fiy-weight, connected to the primary pressure-printing toggleand reacting against another toggle-fulcrum, said type-action furthermore having an easy key-touch in that said operating arm is pointed so that the leverage moment thereof decreases from a maximum which obtains at the beginning of the keylever stroke to a certain least leveragemoment which obtains at the end of thekey-lever stroke.

6. In a typewriting machine, a noiseless, pressure-printing type-action system constituted of a minimum number of parts by the combination of a set of type-carriers, a set of primary toggles, each connected to a corresponding type-carrier and reacting against a fixed toggle-fulcrum, the

primary-toggle member which engages saidtoggle-fulcrum having two operating arms,. by which the primary toggle may be actuated, a secondary toggle, including a momentum-accumulating fly-weight, connected to one of said two operating arms of the primary toggle and reacting against another toggle-fulcrum, said type-carriers and their primary and secondary tog les working in planes radiating forwardly and laterally from the printing-point, a system of type-key-levers disposed below the type-carriers and primary and secondary toggles, each typekey-lever having a branch, the several branches being differentially bent laterally from the keylevers at points differentially located therealong, so that said branches form an array conforming substantially with the radial array of the primary toggles, and a system of links whereby the other one of said two operating arms of each primary toggle is linked directly to the branch of a corresponding key-lever.

7. In a front-print writing machine having a platen, a system of upstanding swinging typebars having types at their upper ends and pivoted at their lower ends, a system of key-levers below the type-bars, power-links extending upwardly from the key-levers, type-bar power-levers radially arranged and articulated to the upper ends of said links, radial toggle-links connecting said power-levers to said type-bars to enable the keylevers to swing the type-bars to the platen, stops for the key-levers, and weighted supplemental toggles anchored to the framework and pivoted to said power-levers to be speeded thereby, to

continue in motion after the arrestof their keylevers, to cause the supplemental toggles to effect supplemental type-pressure, each of the link-connections between the key-levers and the radial power-levers being suiilciently loose to permit supplemental type-pressure to be produced by the supplemental toggle after the arrest of the keylever by its stop.

towards the fulcrum of the power-lever at the arrest of the key-lever by its stop, permitting free supplemental movement of the power-lever and type-bar by the supplemental toggle.

9. In the described portable typewriting machine having a platen, the combination of a system of upstanding type-bars in converging planes in front of theplaten and mounted to swing in said planes to present types to the platen, a system of key-levers below the type-bars, powerlinks driven by said key-levers and extending upwardly in front of the swinging type-bars, power-levers mounted to vibrate in converging planes, the power-links at their upper ends being attached to said power-levers to enable the keylevers to actuate'the latter, a set of radiating toggle-links enabling the key-levers through said power-levers to swing said type-bars to the platen, stops for arresting the key-levers, and weighted means anchored to the framework and pivoted to said radiating power-levers to be speeded thereby, for enabling supplemental pressure to be imparted to the type-bars after the arrest of their keylevers by said stops.

10. In a portable front-writing machine, having a platen, a system of type-presenting and supplemental printing-pressure key-trains, each printing train being compounded of only six elements, viz., a key-lever, a key-powered link rising therefrom, a radial power-lever powered by said key-link, aswinging upstanding type-bar, a toggle-link connecting the type-bar to the said power-lever, and a supplemental weighted pressure device anchored at one end and'connected at'the other end to said power-lever to be speeded thereby, said type-bars, power-levers, togglelin ks and-supplemental pressure devices working in converging planes above said key levers, each power-lever having an outer arm to whichsaid key-powered link is attached, and an inner arm linked to the type-bar bysaid toggle-link.

1. In a typewriting machine, a type-action for printing quietly by means of pressure and a pressure controlling momentum accumulator, said type-action being constituted of a minimum number of parts by the combination of an upstanding radial type-carrier having type at one end and fulcrumed at the other end, a radial power-lever, a toggle-link connecting said powerlever to the type-carrier, said power-lever having two arms, a type-key-lever,- a link directly connecting said type-key-lever to one of said power-lever-arms, and a supplemental weighted toggle anchored at one end to the framework and powered at the other end by the other arm of said power-lever.

12. In a pressure-printing and momentumcontrolle'd type-action for a portable typewriter, an upstanding type-carrier having type at its upper end and fulcrurned at 1.the. lower end; a folded power-toggle connected at one end to the type-carrier and anchored atthe other end, the anchored toggle-member having two operating arms, a type-key-lever, a'drive-link directly con necting said type-key-lever to one of said arms of said toggle-member, a supplemental weighted of said toggle-member to be speeded thereby, and a stop for arresting the printing-stroke of the key-lever just before the type-carrier'prints,

: the momentum of the supplemental toggle be- 8. Machine constructed .according to claim '7, in which each power-link extends substantially the combination with a system of type-keys, of

a system of upstanding type-carrying bars in front of the platen and pivoted to swing their upper ends to present the types to the platen, said type-bars working in planes which converge from front to rear,a system of radiating powerlevers connected to said type-keys and pivoted upon the framework, toggle-links connecting said power-levers and type-bars to enable said keys and power-levers to swing said type-bars to their printing positions, each power-lever and link forming a normally folded toggle, and means operated by each of said power-levers, in the form of a normally folded sub-toggle pivoted at one end to the power-lever to be unfolded thereby, and anchored at the other end to the framework, each sub-toggle being inclusive of a weighted short momentum-link, for effecting supplemental pressure of thetype against the platen.

key and a pull link connected to the key-lever,

the pull link being directly connected to the power-lever to actuate the latter, and means for arresting the down stroke of the key-lever whe its pull link is about in line with the fulcrum 0 its connected power-lever, to permit slight supplemental movement of the power-lever for effecting printing-pressure after the arrest of the key-lever.

15. In a front-print writing machine having a platen, a noiseless, easy key-touch type-action system including a system of upstanding swinging type-bars having types at their upper ends and pivoted at their lower ends, asystem of keylevers below the type-bars, power-links. extending upwardly from the key-levers, type-bar radial power-levers articulated to the upper ends of said links to be powered thereby, radial togglelinks connecting said power-levers to said typebars to enable the key-levers to swing the typebars to the platen, key-stroke stops for the keylevers, and supplemental toggles including elements pivotally anchored to the framework and weighted elements pivoted to said power-levers to be speeded thereby. to continue in motion after the arrest of their key-levers, to cause the supplemental toggles ,to effect supplemental typepressure, each of the power-links between the key-levers and the radial power-levers being arranged to permitsupplemental type-pressure to be produced by the supplemental toggle after the power-levers, said power-levers and said radialtoggle-links cooperating to decelerat the typebars as the latter approach the platen while said power-levers substantially continue to speed the weighted elements of the supplemental toggles, to conduce to noiseless printing by non-' percussive pressure.

1 WILLIAM A. DOBSQN. 

